I have found a mentioning of semantic technologies in this pdf: http://me.jtpollock.us/pubs/2008.05.Pollock.STC.2008.pdf. (published in the year 2008).
And to find out further I have gone through all the manuals at http://download.oracle.com/docs/cd/E12515_02/grc/html/docset.html, but i could not find any details on semantic features.
If these features do exist, are they behind the scene and are transparent to the end user?
I had a look through the document you linked. From your document it seems this is built into the architecture. I don't think the documentation available from the product in eDelivery gives too much detail. On page 22 of the presentation you linked it seems the ontology has been used for the adapter framework, context bindings, and policy engine. I'm guessing this is for added flexibility. It seems the presentation was geared more towards the direction of products who will incorporate this rather than what is there now, and I could be wrong about that.
So to answer your question in short, this looks to be in the engine of the product. You may want to open an SR or something to get further details if you need further information.